Area Lamp in Viewport in Blender Internal Engine
Area lamps, as you may already know are not supported in BGE/UPBGE 0.2x, however we can still bake lighting such as area lamp lighting onto an image.
Cycles bake tutorial. The same can be done with Blender Render, just with different, compatible materials to that particular render engine.
https://www.youtube.com/watch?v=7pcjenAfFto